Bending machine



Dec. 31, 1946. R M,SHA ,JR 2,413,524 BENDING MACHINE Filed Oct. 9, 1943 4 Sheets-Sheet l INVENTOR- Rav/z M. Slzaw, e52,

BY 1kg.

ATTORNEYS.

D 1946- R. M. SHAW, JR 2,413,524

BENDING MACHINE 4 Sheets-Sheet 2 Filed Oct. 9, 1945 |1ll Illlllllllllll! l I l I 'HGAZ i9 5% 32a 55a 35a ATTORNEYS.

Dec. 31, 1946. R. M. SHAW, JR

BENDING MACHINE 4 Sheets-Sheet 3 Filed 001;. 9, 1943 Zia" R. M. SHAW, JR

' BENDING CHINE Filed 00%. 9, 1943 4 Sheets-Sheet 4 R I? I BY '1 1M INVENTOR MJ'klIII/Jn,

anomwz s.

Patented Dec. 31 1946 UNITED STATES- PATENT GFFICE Ralph Ml N; J l, as-

signor to Pedrick Tool & Machine Company; Philadelphia, Pa-., a corporation of Pennsylvania Application October 9, 1943,;Serial'No.505,634

I 1-6 Clai1'ns.

1, This invention relates to machinesuseful more particularly in bendin metalli structural bars or rods ofdifierent cross section, pipes, tub'es, et'c.,

and has reference more specifically to bending" machines of the table type such as disclosed in U. S. Patent No. 2,266,912, granted to machine"- cember 23, 1941.

The chief aim of my present invention'ifs to enhance the utility of bending machines of the Fig: 1 isa fragmentary view in planof one embodiment of my improved bending'fmachine';

Figs. 2, 3 and4 are fragmentary sectional views taken as indicated respectively by the angled airrWsfII- II,'.IIIIII and IVIV in Fig. 1'.

Fig is a viewcorresponding to Fig". 1, showing an alternative embodiment of my invention; and" Figs.6; '7 and 8 are diagrammatic'view in top plan showing how complex bends of changing;

curvature can be made with a machine of'my invention.

With' reference first more especially 1 to" Figs;

1-4; the bending machine'there shown comprises" ment with a drivin'g'pinion l3 journaled in said bed. Suitably fixed'in the bed is a studor'p'os't' M which extends upwardly through a" central ap erture in the turn-table ll. Fulcrumedon the stud or post I4 is an arm. l5"whichrea'chesfto the marginal surface'of the bed. In where itis' fixable against turning about said stud by: a removable latch pin l6 which is selectively 'engag'e'able with socket apertures at intervalscircumferenti'ally'of" said bed; As" shown, the arm [5 has a longitudinally-extendingdove tail slot "along which a block I8 is adjustable bymeans of a screwspin'dle l9. Incorporated with the'lolo( :k'l8 is a holding means in the'form of a quick-releasable manuallyoperable clamp 2flbyfl which at fiat barB of rec'- tangular cross section which is to bebe'nt' is'jse-f cured. in the machine Also fulcrumed' on the stud'lqrpost Maud arranged at opposite sides of the clamp arrnl 5 are arms 22 andZlia which are right anldleft counterpartsof each other. The arm 2'2' has parallel longitudinally-extending dove-tail slots 23 and 24 for guidance of blocks 25and'2'6 which .are adjustable along said slots by screwspindles 2.1 and zfi're'spectively. Mounted on'the block 25. is avertical axis grooved. roller 3'! which-is adapted'to engage one side edge of thebar B; while a-pairof similar groovedrollers 3'2and 33 freely rotatable respectively about studs 34 and 3.5 upstanding from the blookZ-ii, engage theother sideedge of thebar BI It is to-be noted that, when in. operativeposition, the rollers 3i and 3.2 engage the bar B at diagonally opposite points,- while the ro1ler Z=f2 islaterally spaced at afixeddistance-from the roller 3| in a plane at right angles to the armil. At its outer end the arm .22ihas-an apertured lug projection-3:6 for passageof a latch pin 37 wherebyit may besecured to the turn-table H for movement by the latterabout the stud [4. For. the purpose offp'osimay driving; the roller 3|, during certain bending operations, there. is provided-ayariable speed electric motor which isfixedly supported-by the, bl'oc k-2-5 and-which has amit'er gear pinion 39 on it's shaft in meshiwithacompanion miter pinion 4'llilaff ixedlto said roller, The arm 22a is equipped with a group of grooved instrument-alities which are identical with those above described in' connection with the arm :22 but reverselyarranged,- the corresponding. parts being identifie'dlby the same reference numeral with the letter a added'in each instance tenemenience of-more-ready distinction. For operation upon a bar B of flat rectangular cross'sect'ion such 1 as the one illustrated-the rollers 3%, Sta and-32,

32'a' are configured as insta'nced' inFig. 4', i'.f.e., provided with circumferential grooves. of rectangular profileit o c rr spond accurately with-the cross section of said bar." n

In preparation" for thebending, the rollers 3i anfdjSl'a areiadjustedalon gthe arms 22 and 22a relative to'the axis's'tud orp'ost war the machine by means of the screw spindles 2'1 and 21a in aco'orfdalice"with" the radius of the curvature desired, whereupon-theclamp'block. It is shifted inward alongit's} arm labyimeans of. the screw spindle ,l 9 to bifin'g'th'e' inner? edge of' the bar 13 into the" grooves'ofsaid rollerstlf and 35d. 'The blocks? 6 and 2 6a" are rie'xtshifte'd inwardly along the arms: 32' and 22a'jrespectively' by means-of the ad usting crewszs; 23a to time: g- 3'2; swam s", sadintb,en'gagementwiththe outer edge of the bar B. With the parts thus set, the roller arm 22a free, the clamp arm I secured against rotation by the latch pin is and the roller arm 22 locked to the turn-table H by the latch pin 31, said table is rotated in the direction of the curved arrow in Fig. 1. As the arm 22 moves with the turn-table I l for example to the position in which it is shown in dot-and-dash lines, the end portion of the bar B below the clamp arm It as viewed in Fig. 1 is bent at X by the cooperative action of the grooved rollers 31 and 32, the roller 33 serving to keep said bar confined to its original plane. For a short bend, the roller 3! may be allowed to roll freely through traction with the inner edge of the bar B. However, for larger bends up to a semi-circle, the roller 3| is positively driven in the direction'cf the arrow thereon by the motor 38 at a speed somewhat faster than it would ordinarily rotate by traction with the bar B so as to effect a smoothing of the metal of said bar and thereby prevent flattening of the bend as the roller arm 22 continues its movement in the direction of the curved arrow in Fig. 1 beyond the dash-and-dotted line position. The other end portion of the bar B can obviously be bent in a like manner until a com-' plete circle is formed. In preparation for the latter bending step,'the latch pin 31 is withdrawn to free the arm 22 and used to lock the arm 22a to the turn-table II which is thereupon rotated in the direction opposite to that indicated by the curved arrow in Fig. 1.

The radius of the bend in all cases is determined by the distance of the rollers 3i and am from the axis of the machine and not on the distance of the rollers 32 and 33 from the rollers 32a and 33a, and is independent of the dimensions of any of said rollers. The spacing of the rollers 32, 33 and 32a, 33a is for the purpose of changing the leverage, thereby to minimize flattening and wrinkling of the work or bar B as it is being bent, the rollers 33 and 33a serving to convert the single fixed loading of each of the rollers 32 and 33a into uniform distributed load. Th machine thus diflers from the usual forms of roller benders since the arrangement of the roller assemblies is non-pyramidal. The use of two arms 22, 22a as herein shown in especially advantageous in that it allows bends to be made in different planes. of the holder clamp 26 and the peripheries of the grooved rollers 3l-33 and 3la33a, the machine can of course be adapted to bending bars of crosssectional shapes other than the one herein shown by way of example.

By reference once more to Fig. 1, it will be noted that the elements 3| and 31a function as progressively moving die points with the elements 26, 33 and 26a, 33a constituting correspondingly moving points of application of the forces by which the bar B is pressed toward the elements :3! and SI a, and moreover that the bending force or torque of the machine transmitted to the elements 26, 33 and 26a 33a operates against a leverage arm equal to the distance between the axes of the elements 26, 26aand the elements 3|, 3111' respectively. The bending is therefore accomplished by compression rather than by tension, with the neutral axis of the bar B lying outside of the center of gravity. In other words as the bending is progressively effected by coaction between the moving groups of elements 26, 3|, 33 and 26a, 3m, 33a, the bulk of the bar B is subjected to compression without any substantial attendant tensioning of the outside portions of the By suitably shaping the jaws 4 bends. Accordingly, under these circumstances the bending is accomplished with little or no change in the cross section of the bar from its original form and dimensions.

The alternative embodiment of my improved bending machine illustrated in Fig. 5 is generally similar to that of Figs. 1-4, having two arms 22c and 22d respectively with grooved rollers 3lc, 32c, 33c and 3Id, 32d, 33d, but being devoid of the clamp arm t5. Another difierence to be noted is that the end lugs 36c and 36d of the arms are each provided with two apertures so that they may be locked either to the machin bed lfic or to the turn-table He by means of the latch pins 31c, 37d for the reception of which said bed and said table are respectively provided at suitably spaced circumferential intervals with socket holes 43 and 4 5. It will be further noted that here, the adjusting screws 21c, 21d and 28c, 28d have secured to them spur gear pinions 45c, 46c and 45d, 46d respectively with which idler pinions 41c and 41d slidable on studs 43c and 48d at the outer ends of the roller arms 22c and 22d are meshed at certain times for a purpose presently explained. All other elements in the alternative embodiment not specifically referred to but having their counterparts in the first embodiment are, in order to preclude the necessity for repetitive description, identified by the saine'nllmerals but difierentiated by use with them of the letters 0 and d.

The procedure followed in making bends of changing curvature in one operation in the alternative machine of Fig. 5 is as follows: In preparation, the arm 22d is secured against rotation to the machine bed Ific by the latch pin 3112, with the arm 22c positioned alongside it and secured to the table He by the latch pin 370. The rollers 31c and 3ld are next adjusted to the desired positions along the arms 22c and 22d; the bar B engaged with said rollers; the rollers 32c, 33c and 32d, 3311 are then moved inward of said arms to engage the outer edge of said bar, and the spur pinion llc shifted into mesh with pinions 45c and 410 on the spindles 27c, 280 of the arm 220. All being now in readiness with the bar B held by the rollers of arm 2211, the table I I0 is rotated in the direction or the curved arrow in Fig. 5 through a distance say of ninety degrees, whereby the arm 220 is moved to the position in which it is shown in Fig. 6 to form the bend X in the bar B, after which said arm is latched to the bed lllc. With this accomplished, the arm 22d is pinned to the bed lfic'as likewise shown in Fig. 6 and moved to the position in which it is shown in dot-and-dash lines in the last mentioned figure by further rotation of the bed in the same direction as before, and finally re-latched to the bed l 00 to hold the bar B at the terminus of the bend X just completed. The arm 220 is thereupon again latched to the table He and the latter further turned still in the same direction to move the arm 22c say to the position in which it is shown in Fig. '7 and then latched tothe bed I00 and the arm 22d latched to the table I la. The table He is then turned still further in the same direction to bring the. arm 22d alongside the arm 22c and thereafter latched to the bed Hlc to hold the bar B at the terminus of the now completed second portion X of the bend.' Thereupon the arm 220 is relatched to the turn-table He, and the latter turned still further in the same direction to.

anawca.

. incidentally moved inward of the arm'ZZc. progressively by turning; of one of the spindles. 21c and 280 (the other spindlebeing obliged to follow' suit by reason of being connected by the gears-45c; 46c and 410), with the result that a sharper curve is formed in the bar B as shown at X in Fig. 8. These settings and operations are repeated asoften as necessary depending upon thefshaping desired in the bar B; and it is to be understood; that,.bylike manipulations and selective use of the two. arms22c, 22d, the other end portion of the bar may be similarly ,or difierentlyl bent through curvatures of changing radii.

To facilitate complex bending operatings of the kind just described, I provide templates such as the one shown at 50 in Figs. 6-8 to define the lines along which the bends are to be made. The template 50 may be in the form of a suitably profiled plate capable of being removably secured against rotation in the machine to the top of the stud I40 above the roller arms 22c and 22d. It is of course within the province of my invention to substitute power means for actuating the spindles of the arms 22c and 2211 in lieu of the hand wheels herein shown by way of example.

Having thus described my invention, I claim:

1. In a machine for bending bar and the like, an arm movable about a fixed fulcrum; more than two rollers supported by the arm to one side of said fulcrum and relatively adjustable directly along said arm to engage opposite sides of the bar at diagonally related points, as considered with respect to the fulcrum, with one of said rollers serving as a backing means beyond the others and also to confine the bar to its original plane; quick-release holder means for fixedly supporting the bar during the bending operation; and means operatively-coordinated with one of the rollers aforesaid for moving the arm about its fulcrum relative to said holder means.

2. A bending machine according to claim 1, further including means whereby the spaced rollers can be simultaneously adjusted along the supporting arm; and means whereby the bar holder means can be correspondingly adjusted radially of the fulcrum of said arm.

3. A bending machine according to claim 1, wherein the roller supporting arm rotatively includes a pair of longitudinally-extending adjusting screw spindles; wherein followers on the said screw spindles respectively carry an individual and plural rollers; and further including means whereby the bar holder can be adjusted radially of the fulcrum of the arm to correspond with adjustments of the spaced rollers.

4. A bending machine according to claim 1, further including a backing means for contacting one side of the bar at a point beyond one of the spaced rollers transversely of the supporting arm; means whereby a pair of the rollers together With the associated backing means, can be independently or simultaneously adjusted along the supporting arm; and means whereby the holder means can be correspondingly adjusted radially of the fulcrum of the supporting arm.

5. A bending machine according to claim 1, wherein a variable speed motor is provided to drive one of the spaced rollers in the direction it would naturally turn by traction with the bar during the bending operation.

6. A bending machine according to claim 1, wherein a variable speed motor is provided to drive the spaced roller which engages the inner side of the bar in the direction it would naturallyiturn'tby traction with said bar duringv the bending;

- 7. In: aamachine 'for'bending bars andvthe like, a. bed; azfixed: studzupstanding fromsaidi bed; a peripherally-toothed turn-table with means whereby it.-,is,=-rotatable about said: stud; anarm tul'crumed'. on the; studand carrying'more than tWOxliOllGlS setto. engage the outer and the inner sidesoit'heban at diagonally related points; an-

otherearm" with means thereon for holdingthe.

bar-during the bending operation; means whereby the first mentionedarm; can. be releasably secured to the turn-table for'rotation thereby; and means whereby the second mentioned arm can be releasably connected in different positions around the bed beyond the periphery of the turn-table.

8. A bending machine according to claim 7, further including means whereby the several rollers and the holding means can be adjusted along their respective carrying arms.

9. In a machine for bending bars and the like, a bed; a fixed stud upstanding from said bed; a turn-table rotatable about said stud; an arm fulcrumed on'the stud and having means thereon for holding the bar during the bending; a pair of arms independently fulcrumed for movement about the stud, and each carrying a pair of rollers set to engage the bars at diagonally opposite points, the rollers of one of the latter arms being reversely arranged with respect to those of the other arm of the pair; means whereby the holder arm can be releasably secured in different positions around the bed beyond the periphery of the turn-table; and means whereby each arm carrying a pair of rollers can be releasably secured selectively to the turn-table for individual rotation thereby relative to the holder arm.

10. A bending machine according to claim 9, further including means whereby the rollers, and the bar holder means can be individually adjusted along their respective supporting arms,

11. In a machine for bending bars and the like, a bed; a stud upstanding from the bed; a circumferentially toothed turn-table with gear means whereby it is rotatable about said stud; a pair of arms fulcrumed for independent movement about the stud, each said arm carrying bending instrumentalities for engaging the bar from opposite sides at diagonally opposite points; and means whereby said arms can be selectively coupled either to the bed or with the turn-table so that one may be employed as a fixed holder for the bar while the other is moved to effect the bending.

12. In a machine for bending bars and the like, a bed; a stud upstanding from the bed; a turntabl rotatable about said stud; an arm fulcrumed on the stud, said arm carrying a pair of rollers set to engage the outer and inner sides of the bar at diagonally opposite points, a backing means effective to contact the outer side of the bar at a point beyond the outer of the pair of rollers and transversely of the arm; a second arm similarly fulcrumed on the stud and having rollers and a backing means like that of the first arm but reversely arranged thereon; and means whereby said arms can be selectively coupled either with the bed or the turn-table so that one may be employed as a holder for the bar while th other is moved to effect the bending.

13. A bending machine according to claim 12, further including means whereby the roller and the backing means assemblies can be adjusted along their respective carrying arms to vary the curvature of the bending.

able to the fulcrum stud above the two arms for 10 service as'a guide'in adjusting the respective roller assemblies during the bending.

16. In a machine for bending bars and the like,

a fixed fulcrum, a lever arni movable about the fulcrum, said arm carryingmore than-two circumferentially-grooved rotatable elements including one element for engaging the inner side of the bar at a single point, and the other elements for engaging the outer side of the bar at a point beyond the region of contact of the bar by the first mentioned element; means for holding the bar against displacement in the machine dur ing the bending; means for adjusting the respec tive bar engaging elements along the lever arm; and means for moving the arm.

RALPH M. SHAW, JR. 

